Hi,

I recently had MTI's heads & cam done to my car and since that time, I've raced three people. i'm 0-3 and quite disappointed. The problem isn't lack of power- it is lack of traction.

An example:
Today I ran a guy in a modded Z28. I pulled up next to him and noticed he had drag radials on back and skinnies on the front- figured he'd be a good challenge. While going 35mph, we both punched it and it was dead even all the way to 120+. At the next light we stopped and talked-- he was clearly impressed that my corvette had kept up with his drag-strip setup. So we then went to run from the light. Right out of the hole he knocked off about 2 car lengths on me while I sat and spun sideways. Finally I hooked up and he didn't gain anymore but by then it didn't matter as he was well ahead and I wasn't able to pull on him.

After the money I've spent on the heads & cam package, I'm wondering what other mods I need to do for better traction? I'm pretty sure my new rear tires are part of the problem. I have two 315/30R18 Pirelli PZero Rosso Asimmetrico tires. After I bought the tires, I read that the Rosso variant is the "all-weather" version of the asimmetrico tires. Doh. Sure enough, I have unbelievable traction in the wet (better than I've ever had before) but have relatively poor traction when it is dry.

What other things should I look to change? I have bilstein sports and would prefer to keep them unless they are a major problem.

Also, I need to learn how to drive better- ride the edge of traction better rather than always just wildly breaking loose or completely bogging. Any pointers on techniques I can use to help my launch? Also, what tires should I replace these Pirelli's with. Do you think it is even the tires or is it just me? Anyone else with the Rosso's having good luck?

Thanks guys!
Justin

P.S. I still love my heads & cam job- just need to learn how to use it!

 

To me, you ask the most important and hardest to answer question. It is hard enough to answer when just talking about the drag strip, but when you add in the street, it really gets tough.

On the track, Mickey Thompson ET Streets are the best answer. You have to get 16" wheels and do some minor suspension grinding.

ET Streets are NOT for the street.

Nitto drag radials are about the best for the street. They do okay in the wet as well as the dry. You have to get 17" wheels for these. AFS makes some real nice ZR1 style wheels in 11" widths which work nicely.

In either case, you still need to "feel" that perfect spot in the clutch pedal to get maximum power thru the clutch and to the tires without spinning them. Practicee, practice, and more practice.

Good luck.

BTW, with your mods you have one awesome car.

 

Practice - practice - practice :smash:

:cheers:


[Modified by bparker, 9:21 PM 1/6/2002]

 

ambitin, tsk, tsk, man.........what a problem to have :D
Well, like the men say........get ready for some serious rubber, and parts replacing........you gonna be breakin stuff now!!!! :yesnod:
Seriously, that is a problem ALL of us would love to be saddled with......... ;)

 

I agree with Steve Row. Putting down the power you now have will entail drag radials. Here's a BFG perspective.

Yesterday I removed my BFG 315.35.17 drag radials on 12" x 17" wheels ( from John at http://www.ccwheel.com ) and remounted the stock F1SCs on 10.5" wide stock Z06 wheels. Net result is I've lost a lot of straight line traction!!

My BFG DR set up would be great for street racing, if I ever wanted to do such a thing. :D

I actually did a few street launches with TC-on and the BFGs hooked strong enough that TC was not invoked. Not sure how I managed that.

Anyway I'm impressed by this set up for the street and would keep them on but need to save the tread for the dragstrip this Spring.

You can't go wrong with the BFG and John at CCW can do a turn-key set up and ship them at around $1200.

Ranger

 

Ok,

From what I can tell there are two things I can work on:

1) technique
2) wheel/tires setup

Technique is something I can just do every time I'm at a red light with no cops around. Wheels and tires I'll have to think about. Looks like I have to go 17" in the rear to get the best tire selection?

Are different kinds of pavement better/worse for launching?

Lates,
Justin

 

Justin, fresh clean asphalt is stickiest, and concrete is 2nd, stay away from old asphalt(shiny surfaces), and asplaht gravel mix/w/sealer...............
Also, a lot of muni's use crushed granite in the mix, this is a no no also.
Where you live temps shouldn't be much of a concern, unless it's a cold spell. ;)

 

Oh yes. In this cool weather, the black asphalt is worst by far, concrete is best. Even with nearly stock power, my car with the new Pilot Sports, and rschitlz car with new BFG KD's will easily spin all the way through first gear just by hammering the gas with the clutch already fully engaged. (Don't ask ME how I know this about my car AND Rick's) In both cases, this is on asphalt. On concrete, it hooks up much quicker.

Don't forget that anything you do to improve traction for drag racing will have negative effects on your car as a daily driver. The best results would be to get weight to shift to the back of the car. That can be done with shocks - but it would require major compromises for the street.

Keep you gas tank over half tank, and has anyone out their tried moving the battery to the back of the car? Just some thoughts

 

Steve, et. al.,

I noticed that the recommendation for getting better traction meant going with a small wheel... given that a big wheel (19" or even 20") on the C5 is great from a styling standpoint, I wonder what gives the traction advantage when going to a smaller wheel?

Also, what tire offers the best compromise between traction at launch and offering great handling characteristics? I love to blast through twisties in my stock C5, but I can sense a need for better traction "off the line" than my runflats offer.

 

Justin,

I don't think your alone with this problem. Many of the Houston head/cam guys are having the same problem. In fact alot of times when they run, I've seen them go from a third gear roll because of this very issue. IMO, I would stay with a good street tire rather than a drag radial since your car is a daily driver. Maybe you could try the Pilot Sports or KD's next. I'm very impressed with both tires. I think the number one thing is just more practice.

 

You go to a smaller wheel, but taller sidewall on the tire. It allows the tire sidewall to flex and grip better (every watch a drag car with slicks - the tire wrinkles).

Buy the way, I just went to non-run flats and love them. You should do a search on the subject as the subject has been highly debated, and there are good pros and cons both ways.

 

The smaller the rim, the greater the sidewall. The larger sidewall allows the tire to flex and wrinkle a little, helping the contact patch.

As far as your question about tires, I would recommend a good high performance street tire. They will be stickier than the runflats, and offer excellent cornering ability.

Rick

 

Do you guys think going to an 11.5 inch wheel in the rear would help much? 18x11.5? A friend says the BFG Comp T/As at 335/35 fit on those and are comparable to Nitto's.

Rick, yeah, 3rd gear is really the sweet spot- no wheelspin issues there and GOBS of speed :D .

Ok, I know this is a frequently asked question, but what is the widest tire you can wear in the rear without tubbing or sticking out excessively?

Thanks,
Justin

 

The ET Streets are only available in 16" wheel sizes.

BFG's are available up to 17" wheel sizes.

Nitto's until very recently were only available in 17" wheel sizes, but I see now that they are available in one 18" size. Apparently they are making them for the Ford Lightning. The trouble, as noted above, is the lack of sidewall. Also, this tire is almost 2" taller than the 17" sizes. Anything over a 26" tire will have negative affects on performance.

Another option is Hoosier AutoCross tires. I know nothing about these except they do not hook all that well on the Drag strip.

I have Michelin Pilot Sports for street tires and while they are far better than run flats, I can spin them thru 1st and 2nd on the street. My Nitto's spin part way thru 1st and then hook pretty well. This is from a rolling 10-15 mph start. While not designed for cornering, the Nitto's hold a little better thru corners too.

Don't forget practice!

 

Had this same problem on the street with the run flats.

I ran my buddies z06 from a roll and it wasn't a problem, but from a stop I had to ease into the power or else it was spin city.

But after a couple of runs the runflats wouldn't even stick from a roll.

Coming home from the strip I had my drag radials on and met up with a cammed WS-6 and won easily from a roll. At the light I won easily, a lot of it was due to him spinning.

So I guess bigger stickier tires are in your future. :D


[Modified by Scott97, 8:17 AM 1/7/2002]